The Yuanshi Wuliang Duren Shangpin Miaojing Neiyi 元始无量度人上品妙经内义

Yuanshi Wuliang Duren Shangpin Miaojing Neiyi (Inner Meaning of the Supreme Wonderful Scripture of the Primordial Beginning for Delivering Beings Without Limit) Annotated by Xiao Yingsou, a master of the Shangqing School of Taoism in the Southern Song Dynasty.

Consisting of five volumes, it is included in the Yujue (Jade Commentaries) category of the Dongzhen (True Grotto) Section in the Daozang (Taoist Canon).

At the beginning of the book, there are a "Memorial to the Emperor" and an "Essence of the Scripture" written by the author in the second year of the Baoqing reign of Emperor Lizong of the Song Dynasty (1226). In these texts, the author claims that the work synthesizes annotations from four scholars—Yan Dong, Xue Youlou, Cheng Xuanying, and Li Shaowei—and supplements them with theories from his teachers and friends appended to individual phrases to clarify the scripture’s core meanings. Additionally, the book contains three diagrams: Taiji Miaohua Shenling Hundong Chiwen Tu (Diagram of the Mysterious Transformation of the Taiji, Spiritual Beings, and the Mixed Grotto Red Script), Tixiang Yinyang Shengjiang Tu (Diagram of the Substance and Phenomenon of Yin-Yang Ascent and Descent), and Dahuan Xinjing Huohou Tu (Diagram of the Alchemical Fire Regulation in the Great Return Heart Mirror), all illustrating the principles of internal alchemy.

The author argues that "Lingbao and Golden Elixir (Jindan) originate from the same source but bear different names," asserting that the essence of the scripture and the path of internal alchemy are identical and indistinguishable. Thus, the book frequently interprets the scripture through the Yijing (I Ching) scholarship of internal alchemists. For example, the term "Yuanshi" (Primordial Beginning) is explained as the original spirit (yuanshen), true lead (zhenqian), and the mother of elixir refinement. Another instance: beneath each of the sixty-four lines in the "Middle Chapter of the Spiritual Book" (Lingshu Zhongpian), the author attaches a trigram (gua) and a time marker (shigui) to elaborate on alchemical principles and fire regulation (huohou).

This work pioneered the interpretation of the Duren Jing (Scripture of Delivering Beings) through the lens of internal alchemy, exerting considerable influence on subsequent commentators.